1. Field of the Invention
The present invention relates to a power-cord connection set intended primarily for use with electric or electronic equipment.
2. Description of the Related Art
A general power-cord connection set that is well-known in the art includes a plug provided with a pair of plug terminals mounted in a plug case and an outlet provided with a pair of terminal receptors mounted in an outlet case. Various plugs, such as those described in published unexamined Japan patent applications Nos. HEI-8-255651 and 2000-182732, and outlets, such as those described in published unexamined patent application No. 2000-340286, have been proposed. These plugs and outlets are provided with connectors for forming a junction and connecting the lead wires provided in the plug's power cord.
These connection sets are designed primarily for connecting lead wires of electric or electronic equipment. However, neither the power connection (and when necessary the ground connection) nor the connection of the plug and outlet units themselves is sufficiently reliable. If the plug and outlet are left connected for a long period of time, dust might collect at the connection and generate sparks. Further, water entering the connection area might cause a short circuit that can cause a fire.
Because the voltage used in power-cord connection sets having a ground wire is particularly high, the ground wire is designed to eliminate static electricity that is in the plug case and the outlet case that is generated by current flowing through those cases. However, if dust from the surrounding air is electrostatically attracted to the surface of a plug case or outlet case that is charged with static electricity, the dust collecting on the surface can cause sparks at the electrical connecting point between the plug and outlet, resulting in fire.